(a) Field of the Invention
The present invention relates to a tag transmission apparatus and a signal transmitting method thereof.
(b) Description of the Related Art
A passive radio frequency identification (RFID) system does not have an apparatus for allowing a tag having target information to transmit power and a wireless signal. Therefore, the tag constituting the passive RFID system receives a carrier signal from a reader in a wireless environment to generate the power, and performs communications with the reader based on backscattering. Since the passive RFID system may provide information on an individual target body and the like, it may have a greater recognition distance than a barcode, it may simultaneously recognize a plurality of tags, and it has been used in various fields.
The RFID system has recently been used for part management in fields of aviation, automobile manufacturing, shipbuilding, steel production, and the like, and requires a technology for reading and writing mass data at a high speed using a tag user memory of 32 Kbyte, 64 Kbyte, or more. In addition, railway and conveyor application fields require a technology for recognizing an object which is moving at a high speed.
However, the existing passive RFID technology has a limit in satisfying the above-mentioned requirements. The most basic method for transmitting a signal at a high speed is to reduce a pulse width of the signal. Since the tag in the passive RFID system is operated by receiving energy from the reader without having self-power, as a clock speed in the tag is increased, power consumption is increased, thereby causing a drawback that the recognition distance is reduced. That is, a method of increasing a data transmission speed by reducing the pulse width of the signal may have a limit.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.